This paper introduces a formal architecture for onboard diagnosis, prognosis and recovery called ARPHA. ARPHA is designed as part of the ESA/ESTEC study called VERIFIM (Verification of Failure Impact by Model checking). The goal is to allow the design of an innovative on-board FDIR (Fault Detection, Identification and Recovery) process for autonomous systems, able to deal with uncertain system/...

is paper introduces a software prototype called ARPHA for on-board diagnosis, prognosis and recovery. e goal is to allow the design of an innovative on-board FDIR (Fault Detection, Identification and Recovery) process for autonomous systems, able to deal with uncertain system/environment interactions, uncertain dynamic system evolution, partial observability and detection of recovery policies...

Recovery techniques may be distinguished on the basis of the time when the recovery lines are built: at the time of recording the recovery point, at the time of rollback. Consequently we distinguish "planned " and "unplanned" policies for determining recovery lines. With an unplanned policy a "domino effect" can occur. The planned policy is usually intended as being static, in the sense that th...

Overlay multicast can effectively use the Internet as a lower level infrastructure to provide services to members. Overlay multicast is proposed as an alternative approach for providing multicast services in the Internet. In the overlay multicast protocols, each multicast member is responsible for forwarding the multicast packets. Thus, network failure can occur by leaving or joining of nodes. ...

To further elucidate possible central plastic adaptive processes during the recovery from a unilateral peripheral vestibular lesion, we investigated vestibular functions in humans over a period of 2 months after an acute unilateral labyrinthine lesion. A unilateral peripheral vestibular lesion creates both a tonic imbalance that causes spontaneous nystagmus and a decrease and directional asymme...